To deploy the UAV just make sure you're in the commander vehicle first (i.e. Carrier, APC with tent). Right click on the map for the UAV to circle and select the UAV symbol to deploy it to that location. Hit capslock to view (takes a few minutes to deploy).
To zoom in normal view press 1 on the keyboard, and use X to zoom in or out. Press 2 to view it in thermals. This thermal view originally used to allow you as commander to laze targets, looks like its been nerfed in COOP not sure if it works in Deployment because I never tried.
To refuel the UAV before it runs out, right click the UAV button at the top left part of the main screen. Another handy keystroke when trying to work out which squad is which is to press ENTER, you can then view all squad members as per usual.
If the area attack option is available you should see the area attack button building in the top left part of the screen.
The squad leader is the guy that makes an area attack request using his radio. Press 6 , press T and right click for area attack. the aiming is a little bit difficult but you get better with practice.
To accept an area attack, when you see the request for one on the map, once you've checked for friendlies, you can accept or reject the request by right clicking the middle of the concentric circles.
Just remember the area attack has a 200m blast radius so make sure people are warned to clear the area or are in suitable cover such as buildings and bunkers. Iron roof hangars are not safe as I found out on Barracuda the other day. I often use the area attack when I'm at Barracuda at Beach Fortification or Supplies, and my entire squad is under-ground with me. Always a cool way to impress the new players who usually shit themselves when the barrage hits....lol.
As commander it is your responsibility for any team kills that may occur because its your choice to accept or reject the area attack request.
Enjoy!